Focal length is measured in millimeters (mm) and tells you how wide or zoomed a lens is. A short focal length like 18mm shows a wide scene — great for landscapes. A long focal length like 200mm zooms in tight — perfect for wildlife or sports.
You’ll often see lens labels like:
- 18–55mm (a standard kit zoom lens)
- 50mm (a popular fixed or "prime" lens)
- 70–200mm (a telephoto zoom lens)
How Focal Length Affects Your Image
- Field of view: Wide lenses fit more in the frame. Telephoto lenses zoom in.
- Compression: Long lenses flatten distance between subjects. Wide lenses exaggerate space.
- Depth of field: Longer lenses naturally create more background blur.
Choosing the Right Focal Length
- Wide (10–35mm): Landscapes, interiors, street photography
- Standard (35–70mm): Everyday shots, portraits, travel
- Telephoto (70mm and up): Sports, wildlife, distant subjects
Tips
- Zoom with your feet when you can — changing position affects perspective
- Prime lenses (with one focal length) are great for learning composition
- Focal length also affects depth of field, especially with telephoto lenses